Improving a macro value stream is our most challenging & interesting kaizen, in my experience.
A value stream entailing multiple nodes across a continent, or continents, is a complex animal with unknown habits and qualities.
Moreover, it's abstract and often impossible to see in its entirety.
Learning about it is akin to zoology.
We try to make it visible, first with macro value stream maps, then with tabletop simulations using point of sale data.
Then to learn its habits we run experiments & observe what happens.
Each experiment furthers our knowledge & brings us closer to understanding & taming the beast.
Managing our experiments requires a solid governance process - and usually means Level 1, 2 and 3 checking.
(Level 3 might entail the value stream kaizen Steering Team which over time become the value stream managers.)
Are we up to the challenge?
Too often I see organizations defaulting to software solutions.
The mental model appears to be, "The computer will figure it all out for us!"
In effect, they're outsourcing thinking.
Will the computer run the experiments that develop intuition?
Will the computer observe the animal in its natural state and thereby determine its habits and diet?
Remember the Stanley Kubrick movie, 2001 A Space Odyssey?
Remember Hal, the computer, gradually taking over?
"I wouldn't do that if I were you, Dave?"